Thank you for your question.
I think the first thing to be certain of is that you have fat that is available to be dissolved. This is best detected by tensing your neck and pinching under the chin. This shows you how much fat there is under the skin. If there is nothing to pinch there will be no result.
You will be surprised as to how many doctors will not do this basic test only for you to get no result because the contour is down to the shape of the muscle or other reasons.
The answer then depends on the amount of fat you can pinch - if its a lot you will see a small improvement over a number of treatments, if it is very little then the change should be very significant.
We have a very similar product to Kybella called Aqualyx in the UK and swelling is 3-5 days depending really on the bruising more than anything else.
Another option if you have more fat or looser skin is BodyTite/ FaceTite as this technology is very effective in 1 treatment and probably would work out very reasonable.
Dr Dinesh Maini
Zenith Cosmetic Clinics